The diameter of a plant at its equator is 267,100 kilometers. estimate using scientific notation

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

M.xyz =radians. covert this radian measure to its equivalent measure in degrees.

Aclassmate thinks that solving a system by graphing gives an exact answer when the lines appear to cross at a grid point, but only an approximate answer when they don't. explain why this isn't true.